SOLUTION: I am trying to work out this problem as we speak, but I don't know how to figure out the solution part of the problem. Can someone help me out with tis by showing me the correct st

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Question 338980: I am trying to work out this problem as we speak, but I don't know how to figure out the solution part of the problem. Can someone help me out with tis by showing me the correct steps of working this out. Thanks in advance.
2x^2-2x-1=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

2x%5E2-2x-1=0 Start with the given equation.


Notice that the quadratic 2x%5E2-2x-1 is in the form of Ax%5E2%2BBx%2BC where A=2, B=-2, and C=-1


Let's use the quadratic formula to solve for "x":


x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29 Start with the quadratic formula


x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%282%29%28-1%29+%29%29%2F%282%282%29%29 Plug in A=2, B=-2, and C=-1


x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%282%29%28-1%29+%29%29%2F%282%282%29%29 Negate -2 to get 2.


x+=+%282+%2B-+sqrt%28+4-4%282%29%28-1%29+%29%29%2F%282%282%29%29 Square -2 to get 4.


x+=+%282+%2B-+sqrt%28+4--8+%29%29%2F%282%282%29%29 Multiply 4%282%29%28-1%29 to get -8


x+=+%282+%2B-+sqrt%28+4%2B8+%29%29%2F%282%282%29%29 Rewrite sqrt%284--8%29 as sqrt%284%2B8%29


x+=+%282+%2B-+sqrt%28+12+%29%29%2F%282%282%29%29 Add 4 to 8 to get 12


x+=+%282+%2B-+sqrt%28+12+%29%29%2F%284%29 Multiply 2 and 2 to get 4.


x+=+%282+%2B-+2%2Asqrt%283%29%29%2F%284%29 Simplify the square root (note: If you need help with simplifying square roots, check out this solver)


x+=+%282%2B2%2Asqrt%283%29%29%2F%284%29 or x+=+%282-2%2Asqrt%283%29%29%2F%284%29 Break up the expression.


x+=+%281%2Bsqrt%283%29%29%2F%282%29 or x+=+%281-sqrt%283%29%29%2F%282%29 Reduce.


So the solutions are x+=+%281%2Bsqrt%283%29%29%2F%282%29 or x+=+%281-sqrt%283%29%29%2F%282%29


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website.

Jim